#include <stdio.h>

int get_max(int a, int b)
{
    return a > b ? a : b;
}

int calculate(int before, char oper, int end)
{
    switch (oper)
    {
    case '+':
        return before + end;
        break;
    case '-':
        return before - end;
        break;
    case '*':
        return before * end;
        break;
    case '/':
        return before / end;
        break;
    case '%':
        return before % end;
        break;
    default:
        return -1;
        break;
    }
}

void print_graphical()
{
    printf("**********************************************\n"
           "***1. 增加  2. 删除  3. 修改  4.查看  5.退出 ***\n"
           "**********************************************");
}

int main(int argc, char const *argv[])
{
    int max_value = get_max(100, 200);
    int cal = calculate(9, '%', 5);
    print_graphical();
    putchar('\n');
    printf("max value = %d, calc value = %d\n", max_value, cal);
    return 0;
}
